Silo unloaders of the type with which the present invention is concerned have an unloader mechanism with three generally radially extending horizontal support arms to receive cables by which the unloader mechanism is suspended from a tripod in the top of the silo for vertical movement under the control of a winch which is near the bottom of the silo wall. Each cable is trained over a sheave that is journalled in a yoke freely suspended at the upper end of the tripod leg, and because of the way the suspension cables must run from the winch to the sheaves, the sheave yokes are displaced from a vertical position by the weight of the silo unloader on the cables. Heretofore the support arms have been constructed for securement of the suspension cables thereto at points directly beneath the suspension points of the sheave yokes. This is the simplest arrangement, because the cables are secured to points which are in exactly the same location on all three support arms. The arms may all be alike and thus may be interchangeable. As a result of the displacement of the yokes from a vertical suspension, the above described arrangement for securing the cables to the unloader mechanism support arms causes the cables to deviate from a true vertical line by the amount of the yoke displacement. This is an insignificant matter when the unloader mechanism is fairly low in the silo, but becomes progressively more important as the unloader mechanism is raised to a position closer to the tripod. When the unloader mechanism is fully elevated to get it out of the way for loading the silo, the suspension cable runs below the sheaves are so short that the angle of displacement places very undesirable lateral stresses upon the tripod legs.